In low hills of Uttarkashi district 47 traps (VL Kurmula Trap-1) were installed in four villages and one experimental farm .These traps installed in last week of may to first week of June, 2006 on strategic locations because after this monsoon has come and then beetles emergence start. This emergence are continue upto September month. The result showed that beetles traped in I^st year (Year 2006) were maximum on experimental farm (0.28 lakh), Galari village (0.26 lakh), Mahargaon village (0.25 lakh) and fallowed by Tuliyara village (0.24 lakh) and Barethi village (0.22 lakh) The total beetles trapped in lower hills were 1.25 lakh in year 2006. Which showed the reduction in grub population in (damaging stage) were approximately 18.75 lakh. The 2_^nd year (Year 2007) maximum trapped beetles were 0.15 lakh in village Mahargaon and Barethivillage and followed by Tuliyara, Galari village and experimental farm i.e. 0.14 lakh. The total beetles trapped 2_^nd year were 0.72 lakh mean approximately 10.80 lakh grub population reduced. The 3_^rd year (Year 2008) maximum beetles trapped from experimental farm (0.10 lakh) and followed by Barethi village (0.70 lakh), village Mahargaon (0.06 lakh), Tuliyara (0.4 lakh) and Galari (0.4 lakh). The total beetles trapped in year 2008 were 0.31 lakh means grub population reduced approximately upto 4.65 lakh. Reduction in beetles population to the tune of 42.12 and 75.79 per cent was recorded during 2007 and 2008 respectively over the beetle catches of 2006 (Table 1). The peak period of beetle emergence was July in Uttarakhand hills. Three year study revealed that 36 species of white grub beetles were recorded in low hills,in which Anomala dimidiata, A. rugosa, A. tristis, Holotrichia longipennis, H. seticollis and Xylotrupes gideon were dominant. A complex of white grub species has been recorded in Uttarakhand hills, where some of the species cause extensive damage to crop plants (Sushilet al., 2008). The present investigation for the management of white grubs targets two vulnerable stages of the pest viz., adult and grub stages. The two pronged strategy resulted in a significant reduction in the white grub population as evidenced by about 80% reduction in beetle population within 2 to 3 years evidenced by about 80% reduction in beetle population within 2 to 3 years on entire village basis. Light based insect traps have been reported to be effective tool for mass trapping of the scarab beetles by other researchers too (Carne et al., 1956; Kato et al., 2000). Light based insect traps, unlike pheromone traps, are known to attract insects of both sexes of the scarabaeid (Harai et al., 2000 ) and this is in conformity of the findings of the present study, wherein both the sexes of more than 50 species of scarabaeids have been recorded through the light traps. The trap is specific to the scarabaeids and was found to trap negligible number of beneficial insects.

1.2 Management of grub stage

Reduction of grub population over the years was recorded in four adopted villages and one experimental farm through pit sampling. Among the adopted villages of low hills, population of white grubs recorded in the all the locationTable 2~Table 6 and Table 7. Crop wise pit sampling data revealed a substantial reduction of white grub population over the years. The grub population was very high in June 2006, which went up to 2.6 grubs/ 30 cm_² in tomato, 2.3 in potato and 1.6 in French bean. However, due to the continuous mass trapping of beetles and application of the bio-agent, B. cereus strain WGPSB-2 through FYM, a remarkable reduction in the grub population to a tune of 0.6 grubs/30 cm^₂ in Aug 2007 and 0.4 grubs/30 cm_² in Aug 2008 were recorded in tomato fields. By the end of the cropping season in 2008, the grub population was reduced to 0.2 and 0.4/30 cm_² in potato and French bean fields, respectively. The mean per cent reduction in the grub population was 75.4% by the end of second year and it reduced further up to 83. 6% by the end of the third year. Similar trend was recorded in the other adopted villages of low hills. Crop wise pit sampling from the WGPSB-2 applied field, data showed that consistence decrease in the population of the grubs in the all the adopted villages. However in starting of the experiment, population was almost some or marginally high in non-adopted village. Based on periodic pit sampling, the overall reduction of grub population ranged from 70.5 to 84.3% in low hills of Uttarakhand state with a significant increase in crop yield.

Mean yield of different crops was recorded in all the villages and per cent increase in yield of the adopted villages was calculated and compared with the non-adopted villages of different altitudes. Data presented in the Table 8, reveal the per cent increase in yield of different crops in the adopted villages over non-adopted villages. The mean per cent increase in yield in adopted villages were 51.7 in tomato, 46.4 in potato, 39.0 in chilli and 59.2 in French bean was recorded during the three years of experimentation over non adopted village.